05. The flow in a pipe is laminar, when Reynold number is less than 2000. A) True B) False

05. The flow in a pipe is laminar, when Reynold number is less than 2000.
A) True
B) False
by

1 Answer

Answer :

A
by

Related questions

The flow in a pipe is neither laminar nor turbulent when Reynold number is (A) Less than 2000 (B) Between 2000 and 2800 (C) More than 2800 (D) None of these

Description : The flow in a pipe is neither laminar nor turbulent when Reynold number is (A) Less than 2000 (B) Between 2000 and 2800 (C) More than 2800 (D) None of these

Last Answer : Answer: Option B

The flow in a pipe is turbulent when Reynold number is (A) Less than 2000 (B) Between 2000 and 2800 (C) More than 2800 (D) None of these

Description : The flow in a pipe is turbulent when Reynold number is (A) Less than 2000 (B) Between 2000 and 2800 (C) More than 2800 (D) None of these

Last Answer : Answer: Option C

A large Reynold number is indication of (A) Smooth and streamline flow (B) Laminar flow (C) Steady flow (D) Highly turbulent flow

Description : A large Reynold number is indication of (A) Smooth and streamline flow (B) Laminar flow (C) Steady flow (D) Highly turbulent flow

Last Answer : Answer: Option D

The loss of head due to friction in a pipe of uniform diameter in which a viscous flow is taking place, is (where RN = Reynold number) (A) 1/RN (B) 4/RN (C) 16/RN (D) 64/RN

Description : The loss of head due to friction in a pipe of uniform diameter in which a viscous flow is taking place, is (where RN = Reynold number) (A) 1/RN (B) 4/RN (C) 16/RN (D) 64/RN

Last Answer : Answer: Option C

For pipes, laminar flow occurs when Reynolds number is (A) Less than 2000 (B) Between 2000 and 4000 (C) More than 4000 (D) Less than 4000

Description : For pipes, laminar flow occurs when Reynolds number is (A) Less than 2000 (B) Between 2000 and 4000 (C) More than 4000 (D) Less than 4000

Last Answer : Answer: Option A

In case of hydraulically smooth pipe, the resistance to flow depends only on the Reynolds number, whereas for a hydraulically rough pipe, the resistance to flow is governed by the relative roughness. Two pipes are said to have the same hydraulic roughness, when they have equal values of (A) Relative roughness (B) Absolute roughness (C) Friction co-efficient for flows at equal Reynold number (D) All (A), (B) & (C)

Description : In case of hydraulically smooth pipe, the resistance to flow depends only on the Reynolds number, whereas for a hydraulically rough pipe, the resistance to flow is governed by the relative roughness. Two pipes are said ... co-efficient for flows at equal Reynold number (D) All (A), (B) & (C)

Last Answer : (C) Friction co-efficient for flows at equal Reynold number

The velocity corresponding to Reynold number of 2000 is called (A) Sub-sonic velocity (B) Super-sonic velocity (C) Lower critical velocity (D) Higher critical velocity

Description : The velocity corresponding to Reynold number of 2000 is called (A) Sub-sonic velocity (B) Super-sonic velocity (C) Lower critical velocity (D) Higher critical velocity

Last Answer : Answer: Option C

During the opening of a valve in a pipe line, the flow is (A) Steady (B) Unsteady (C) Uniform (D) Laminar

Description : During the opening of a valve in a pipe line, the flow is (A) Steady (B) Unsteady (C) Uniform (D) Laminar

Last Answer : Answer: Option B

The loss of head due to viscosity for laminar flow in pipes is (where d = Diameter of pipe, l = Length of pipe, v w = Specific weight of the flowing liquid) (A) 4 (B) 8 (C) 16 (D) 32

Description : The loss of head due to viscosity for laminar flow in pipes is (where d = Diameter of pipe, l = Length of pipe, v w = Specific weight of the flowing liquid) (A) 4 (B) 8 (C) 16 (D) 32

Last Answer : Answer: Option D

Consider the following statements in respect of steady laminar flow through a circular pipe: 1. Shear stress is zero on the central axis of the pipe 2. Discharge varies directly with the viscosity of the fluid 3. Velocity is maximum at the centre of the pipe. 4. Hydraulic gradient varies as the square of the mean velocity of flow. Which of these statements are correct? (a) 1, 2 , 3 & 4 (b) 1 & 3 only (c) 2 & 4 only (d)3 & 4 only

Description : Consider the following statements in respect of steady laminar flow through a circular pipe: 1. Shear stress is zero on the central axis of the pipe 2. Discharge varies directly with the viscosity of the fluid 3. Velocity is maximum at the ... 2 , 3 & 4 (b) 1 & 3 only (c) 2 & 4 only (d)3 & 4 only

Last Answer : (b) 1 & 3 only

In turbulent flow, a rough pipe has the same friction factor as a smooth pipe (A) In the zone of complete turbulence (B) When the roughness projections are much smaller than the thickness of the laminar film (C) Everywhere in the transition zone (D) When the friction factor is independent of the Reynold's number

Description : In turbulent flow, a rough pipe has the same friction factor as a smooth pipe (A) In the zone of complete turbulence (B) When the roughness projections are much smaller than the thickness of ... ) Everywhere in the transition zone (D) When the friction factor is independent of the Reynold's number

Last Answer : (B) When the roughness projections are much smaller than the thickness of the laminar film

For a given Reynold number as d/D for an orifice increases, Cd will (where, d & D are orifice & pipe diameters respectively). (A) Increase (B) Decrease (C) Remain constant (D) Either (A) or (B); depends on other factors

Description : For a given Reynold number as d/D for an orifice increases, Cd will (where, d & D are orifice & pipe diameters respectively). (A) Increase (B) Decrease (C) Remain constant (D) Either (A) or (B); depends on other factors

Last Answer : (A) Increase

Nusselt number for full developed, laminar, constant property flow in a pipe at uniform heat flux is (A) 0.72 (B) 4.364 (C) 18 (D) 83

Description : Nusselt number for full developed, laminar, constant property flow in a pipe at uniform heat flux is (A) 0.72 (B) 4.364 (C) 18 (D) 83

Last Answer : (B) 4.364

The Nusselt number for fully developed (both thermally and hydrodynamically) laminar flow through a circular pipe whose surface temperature remains constant is (A) 1.66(B) 88.66 (C) 3.66 (D) Dependent on NRe only

Description : The Nusselt number for fully developed (both thermally and hydrodynamically) laminar flow through a circular pipe whose surface temperature remains constant is (A) 1.66 (B) 88.66 (C) 3.66 (D) Dependent on NRe only

Last Answer : (C) 3.66

The Nusselt number for fully developed (both thermally and hydrodynamically) laminar flow through a circular pipe, where the wall heat flux is constant, is(A) 2.36(B) 4.36(C) 120.36(D) Dependent on NRe only

Description : The Nusselt number for fully developed (both thermally and hydrodynamically) laminar flow through a circular pipe, where the wall heat flux is constant, is (A) 2.36 (B) 4.36 (C) 120.36 (D) Dependent on NRe only

Last Answer : (B) 4.36

When the pipe Reynold's number is 6000, the flow is generally (A) Viscous(B) Laminar(C) Turbulent(D) Transition

Description : When the pipe Reynold's number is 6000, the flow is generally (A) Viscous (B) Laminar (C) Turbulent (D) Transition

Last Answer : (C) Turbulent

Pick out the wrong statement. (A) The shear stress at the pipe (dia = D, length = L) wall in case of laminar flow of Newtonian fluids is (D/4L). ∆p (B) In the equation, T. gc = k. (du/dy) n the value of 'n' for pseudoplastic and Dilatant fluid are < 1 and >1 respectively (C) Shear stress for Newtonian fluid is proportional to the rate of shear in the direction perpendicular to motion (D) With increase in the Mach number >0.6, the drag co-efficient decreases in case of compressible fluids

Description : Pick out the wrong statement. (A) The shear stress at the pipe (dia = D, length = L) wall in case of laminar flow of Newtonian fluids is (D/4L). ∆p (B) In the equation, T. gc = k. ... to motion (D) With increase in the Mach number >0.6, the drag co-efficient decreases in case of compressible fluids

Last Answer : (D) With increase in the Mach number >0.6, the drag co-efficient decreases in case of compressible fluids

Fanning friction factor for laminar flow of fluid in a circular pipe is (A) Not a function of the roughness of pipe wall (B) Inversely proportional to Reynolds number (C) Both (A) & (B) (D) Neither (A) nor (B)

Description : Fanning friction factor for laminar flow of fluid in a circular pipe is (A) Not a function of the roughness of pipe wall (B) Inversely proportional to Reynolds number (C) Both (A) & (B) (D) Neither (A) nor (B)

Last Answer : (C) Both (A) & (B)

The characteristic dimensionless groups for heat transfer to a fluid flowing through a pipe in laminar flow are (A) Re.Gz (B) Nu, Pr (C) Nu, Pr, Re (D) Nu, Gz

Description : The characteristic dimensionless groups for heat transfer to a fluid flowing through a pipe in laminar flow are (A) Re.Gz (B) Nu, Pr (C) Nu, Pr, Re (D) Nu, Gz

Last Answer : (D) Nu, Gz

In case of laminar flow of fluid through a circular pipe, the (A) Shear stress over the cross-section is proportional to the distance from the surface of the pipe (B) Surface of velocity distribution is a paraboloid of revolution, whose volume equals half the volume of circumscribing cylinder (C) Velocity profile varies hyperbolically and the shear stress remains constant over the cross-section (D) Average flow occurs at a radial distance of 0.5 r from the centre of the pipe (r = pipe radius)

Description : In case of laminar flow of fluid through a circular pipe, the (A) Shear stress over the cross-section is proportional to the distance from the surface of the pipe (B) Surface of velocity distribution is a ... occurs at a radial distance of 0.5 r from the centre of the pipe (r = pipe radius)

Last Answer : (B) Surface of velocity distribution is a paraboloid of revolution, whose volume equals half the volume of circumscribing cylinder

The ratio of average fluid velocity to the maximum velocity in case of laminar flow of a Newtonian fluid in a circular pipe is (A) 0.5 (B) 1 (C) 2 (D) 0.66

Description : The ratio of average fluid velocity to the maximum velocity in case of laminar flow of a Newtonian fluid in a circular pipe is (A) 0.5 (B) 1 (C) 2 (D) 0.66

Last Answer : (A) 0.5

Assuming flow to be laminar, if the diameter of the pipe is halved, then the pressure drop will (A) Increase (B) Decrease (C) Remain same (D) Be quadrupled

Description : Assuming flow to be laminar, if the diameter of the pipe is halved, then the pressure drop will (A) Increase (B) Decrease (C) Remain same (D) Be quadrupled

Last Answer : (A) Increase

Pick out the wrong statement. (A) The form drag is dependent upon the occurrence of a wake (B) The shear stress at any given cross-section of a pipe for steady flow (either laminar or turbulent) varies linearly as the radial distance (C) An ideal fluid is the one, which has negligible surface tension and obeys the Newton's law of viscosity (D) Existence of the boundary layer in fluid flow is because of viscosity of the fluid

Description : Pick out the wrong statement. (A) The form drag is dependent upon the occurrence of a wake (B) The shear stress at any given cross-section of a pipe for steady flow (either laminar or turbulent ... of viscosity (D) Existence of the boundary layer in fluid flow is because of viscosity of the fluid

Last Answer : (C) An ideal fluid is the one, which has negligible surface tension and obeys the Newton's law of viscosity

For laminar flow of Newtonian fluids through a circular pipe, for a given pressure drop and length & diameter of pipe, the velocity of fluid is proportional to (where, μ = fluid viscosity ) (A) μ (B) 1/μ (C) √μ (D) 1/√μ

Description : For laminar flow of Newtonian fluids through a circular pipe, for a given pressure drop and length & diameter of pipe, the velocity of fluid is proportional to (where, μ = fluid viscosity ) (A) μ (B) 1/μ (C) √μ (D) 1/√μ

Last Answer : (B) 1/μ

What is the ratio of total kinetic energy of fluid passing per second to the value obtained on the basis of average velocity (for laminar flow through a circular pipe)? (A) 0.5 (B) 1 (C) 1.5 (D) 2

Description : What is the ratio of total kinetic energy of fluid passing per second to the value obtained on the basis of average velocity (for laminar flow through a circular pipe)? (A) 0.5 (B) 1 (C) 1.5 (D) 2

Last Answer : (D) 2

The fluid velocity varies as the cube of the cylindrical pipe diameter in case of steady state laminar flow at constant pressure drop for __________ fluid. (A) Newtonian (B) Pseudo-plastic (C) Dilatent (D) Bingham plastic

Description : The fluid velocity varies as the cube of the cylindrical pipe diameter in case of steady state laminar flow at constant pressure drop for __________ fluid. (A) Newtonian (B) Pseudo-plastic (C) Dilatent (D) Bingham plastic

Last Answer : (B) Pseudo-plastic

For laminar flow of a shear thinning liquid in a pipe, if the volumetric flow rate is doubled, the pressure gradient will increase by a factor of (A) 2 (B) < 2 (C) > 2 (D) 1/2

Description : For laminar flow of a shear thinning liquid in a pipe, if the volumetric flow rate is doubled, the pressure gradient will increase by a factor of (A) 2 (B) < 2 (C) > 2 (D) 1/2

Last Answer : (A) 2

The fluid velocity varies as the square of the cylindrical pipe diameter, in case of steady state laminar flow at constant pressure drop, for __________ fluid. (A) Newtonian (B) Dilatant (C) Pseudo-plastic (D) Non-Newtonian

Description : The fluid velocity varies as the square of the cylindrical pipe diameter, in case of steady state laminar flow at constant pressure drop, for __________ fluid. (A) Newtonian (B) Dilatant (C) Pseudo-plastic (D) Non-Newtonian

Last Answer : (A) Newtonian

The Prandtl mixing length is (A) Zero at the pipe wall and is a universal constant (B) Independent of radial distance from the pipe axis (C) Independent of the shear stress (D) Useful for computing laminar flow problems

Description : The Prandtl mixing length is (A) Zero at the pipe wall and is a universal constant (B) Independent of radial distance from the pipe axis (C) Independent of the shear stress (D) Useful for computing laminar flow problems

Last Answer : (D) Useful for computing laminar flow problems

Discharge in laminar flow through a pipe varies (A) As the square of the radius (B) Inversely as the pressure drop (C) Inversely as the viscosity (D) As the square of the diameter

Description : Discharge in laminar flow through a pipe varies (A) As the square of the radius (B) Inversely as the pressure drop (C) Inversely as the viscosity (D) As the square of the diameter

Last Answer : (A) As the square of the radius

For laminar flow of Newtonian fluid in a circular pipe, the velocitydistribution is a function of the distance 'd' measured from the centre line ofthe pipe, and it follows a __________ relationship.(A) Logarithmic(B) Parabolic(C) Hyperbolic(D) Linear

Description : For laminar flow of Newtonian fluid in a circular pipe, the velocitydistribution is a function of the distance 'd' measured from the centre line of the pipe, and it follows a __________ relationship. (A) Logarithmic (B) Parabolic (C) Hyperbolic (D) Linear

Last Answer : (B) Parabolic

The fluid velocity varies as the square root of the cylindrical pipe diameter in case of steady state laminar flow at constant pressure drop of __________ fluid. (A) Dilatent (B) Pseudo-plastic (C) Bingham plastic (D) Newtonian

Description : The fluid velocity varies as the square root of the cylindrical pipe diameter in case of steady state laminar flow at constant pressure drop of __________ fluid. (A) Dilatent (B) Pseudo-plastic (C) Bingham plastic (D) Newtonian

Last Answer : (A) Dilatent

Prandtl mixing length is (A) Applicable to laminar flow problems (B) A universal constant (C) Zero at the pipe wall (D) None of these

Description : Prandtl mixing length is (A) Applicable to laminar flow problems (B) A universal constant (C) Zero at the pipe wall (D) None of these

Last Answer : (C) Zero at the pipe wall

The pressure drop per unit length for laminar flow of fluid through a long pipe is proportional to (where, A = cross-sectional area of the pipe & D = Diameter of the pipe) (A) A (B) D (C) 1/A (D) 1/A2

Description : The pressure drop per unit length for laminar flow of fluid through a long pipe is proportional to (where, A = cross-sectional area of the pipe & D = Diameter of the pipe) (A) A (B) D (C) 1/A (D) 1/A2

Last Answer : (C) 1/A

Transition from laminar flow to turbulent flow in fluid flow through a pipe does not depend upon the (A) Length of the pipe (B) Diameter of the pipe (C) Density of the fluid (D) Velocity of the fluid

Description : Transition from laminar flow to turbulent flow in fluid flow through a pipe does not depend upon the (A) Length of the pipe (B) Diameter of the pipe (C) Density of the fluid (D) Velocity of the fluid

Last Answer : (A) Length of the pipe

Aerodynamic noise resulting from turbulent gas flow is the most prevalent source of valve noise in fluid flow control. It is caused due to (A) Reynold stresses (B) Shear forces (C) Both (A) & (B) (D) Neither (A) nor (B)

Description : Aerodynamic noise resulting from turbulent gas flow is the most prevalent source of valve noise in fluid flow control. It is caused due to (A) Reynold stresses (B) Shear forces (C) Both (A) & (B) (D) Neither (A) nor (B)

Last Answer : (C) Both (A) & (B)

05. In an internal mouthpiece, if the jet after contraction expands and fills up the whole mouthpiece, then the mouthpiece is said to be running free. A) True B) False

Description : 05. In an internal mouthpiece, if the jet after contraction expands and fills up the whole mouthpiece, then the mouthpiece is said to be running free. A) True B) False

Last Answer : B

05. In an internal mouthpiece, if the jet after contraction expands and fills up the whole mouthpiece, then the mouthpiece is said to be running free. A) True B) False

Description : 05. In an internal mouthpiece, if the jet after contraction expands and fills up the whole mouthpiece, then the mouthpiece is said to be running free. A) True B) False

Last Answer : A

The velocity corresponding to Reynold number of 2800, is called (A) Sub-sonic velocity (B) Super-sonic velocity (C) Lower critical velocity (D) Higher critical velocity

Description : The velocity corresponding to Reynold number of 2800, is called (A) Sub-sonic velocity (B) Super-sonic velocity (C) Lower critical velocity (D) Higher critical velocity

Last Answer : Answer: Option D

Reynolds number for flow of water at room temperature through 2 cm dia pipe at an average velocity of 5 cm/sec is around (A) 2000 (B) 10(C) 100 (D) 1000 Answer:

Description : Reynolds number for flow of water at room temperature through 2 cm dia pipe at an average velocity of 5 cm/sec is around (A) 2000 (B) 10 (C) 100 (D) 1000 Answer:

Last Answer : (D) 1000

For pipes, turbulent flow occurs when Reynolds number is(A) Less than 2000 (B) Between 2000 and 4000 (C) More than 4000 (D) Less than 4000

Description : For pipes, turbulent flow occurs when Reynolds number is (A) Less than 2000 (B) Between 2000 and 4000 (C) More than 4000 (D) Less than 4000

Last Answer : Answer: Option C

Derivation of Thiem's formula Q = 2 (s1 - s2)/2.3 log10 (r2/r1) is based on the assumption (A) The aquifer is homogeneous, isotropic and of infinite depth and area (B) The well is sunk through the full depth of the aquifer (C) The flow lines are radial and horizontal, and the flow is laminar (D) All the above

Description : Derivation of Thiem's formula Q = 2 (s1 - s2)/2.3 log10 (r2/r1) is based on the assumption  (A) The aquifer is homogeneous, isotropic and of infinite depth and area  (B) The well is sunk ... (C) The flow lines are radial and horizontal, and the flow is laminar  (D) All the above 

Last Answer : (D) All the above 

A flow in which the viscosity of fluid is dominating over the inertia force is called (A) Steady flow (B) Unsteady flow (C) Laminar flow (D) Turbulent flow

Description : A flow in which the viscosity of fluid is dominating over the inertia force is called (A) Steady flow (B) Unsteady flow (C) Laminar flow (D) Turbulent flow

Last Answer : Answer: Option C

Which of the following is an example of laminar flow? (A) Underground flow (B) Flow past tiny bodies (C) Flow of oil in measuring instruments (D) All of these

Description : Which of the following is an example of laminar flow? (A) Underground flow (B) Flow past tiny bodies (C) Flow of oil in measuring instruments (D) All of these

Last Answer : Answer: Option D

Flow occurring in a pipeline when a valve is being opened is (A) Steady (B) Unsteady (C) Laminar (D) Vortex

Description : Flow occurring in a pipeline when a valve is being opened is (A) Steady (B) Unsteady (C) Laminar (D) Vortex

Last Answer : Answer: Option B

General energy equation holds for (A) Steady flow (B) Turbulent flow (C) Laminar flow (D) Non-uniform flow

Description : General energy equation holds for (A) Steady flow (B) Turbulent flow (C) Laminar flow (D) Non-uniform flow

Last Answer : Answer: Option D

When the flow parameters at any given instant remain same at every point, then flow is said to be (A) Quasi-static (B) Steady state (C) Laminar (D) Uniform

Description : When the flow parameters at any given instant remain same at every point, then flow is said to be (A) Quasi-static (B) Steady state (C) Laminar (D) Uniform

Last Answer : Answer: Option D

The velocity at which the laminar flow stops, is known as (A) Velocity of approach (B) Lower critical velocity (C) Higher critical velocity (D) None of these

Description : The velocity at which the laminar flow stops, is known as (A) Velocity of approach (B) Lower critical velocity (C) Higher critical velocity (D) None of these

Last Answer : Answer: Option B

Normal depth in open channel flow is the depth of flow corresponding to (A) Steady flow (B) Unsteady flow (C) Laminar flow (D) Uniform flow

Description : Normal depth in open channel flow is the depth of flow corresponding to (A) Steady flow (B) Unsteady flow (C) Laminar flow (D) Uniform flow

Last Answer : Answer: Option D